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when i tried to georeference a printout from map.geo.admin.ch, either the result got turned some degrees, or the height got compressed or both.

using the helmert transformation gave me the best results. the result was not compressed - only rotated.

it then looks like: enter image description here

the coordinates for the reference points i userd were taken from the coordinate grid on the website. i used the four corners. top left: 46.86851 9.99669 bottom left: 46.76063 9.99157 bottom right: 46.75528 10.22048 top right: 46.86315 10.22609

i tried it with a screenshot of google maps with the same results... is there a way to georeference that print without rotating it?

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  • Can you add how you picked your coordinates, and what CRS settings you have used?
    – AndreJ
    Jun 19 '16 at 16:48
  • Why georeference a TIFF when you can use a WMS or WMTS ? www.swisstopo.ch/webaccess
    – geofoo
    Jun 20 '16 at 6:07
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The website lets you choose between CH1903+LV95, WGS84, UTM and MGRS coordinates.

Since the map is originally in CH1903+, I suggest to use that CRS and the meter coordinates of it. You can choose to imprint a coordinate grid, which is also in CH1903.

You have to set EPSG:2056 in the georeferencer settings dialogue.

In the part of Switzerland you downloaded, the CH1903 grid is rotated against the degree grid, so that is why you get a rotated image in degree coordinates.

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  • thanks! i did use CRS CH1903+, but added the coordinates as wgs84. as you suggested, i used the meter coordinates now, but the raster got streched now (in contrast to beeing compressed before)...
    – marcin
    Jun 19 '16 at 19:11
  • also, when i used WGS84, the raster was compressed, but it showed my location accurately (using my maps for android) - now, with meter coordinates, the app says my location is not on the map...
    – marcin
    Jun 19 '16 at 19:18
  • please ignore both my comments - i noticed, in the WGS84 format, they use North/East, but in CH1903+ they use East/North... now it works.
    – marcin
    Jun 19 '16 at 19:36
  • @marcin you can still delete your comments if you realize you thought wrong.
    – AndreJ
    Jun 20 '16 at 5:31

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